"What are the most common reliability issues with the John Cooper Works package?"

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Great question! The 2004 Mini Cooper S John Cooper Works package has several well-documented reliability quirks. Here are the most common issues:

**Top Reliability Concerns:**

1. **Supercharger Issues** - The Eaton M45 unit can fail due to oil degradation and housing leaks. JCW models may see this more due to higher boost pressures.

2. **Thermostat Housing Failure** - The plastic housing cracks and leaks on most R53s, leading to overheating if not caught early.

3. **Power Steering Pump Failure** - Very common on 2004 models, often leaving you without power assist.

4. **Cooling System Problems** - The auxiliary fan thermostat fails, causing overheating in stop-and-go traffic.

5. **Clutch Wear** - The Getrag 6-speed's clutch wears faster on track-driven JCW cars.

6. **Ignition Coil Failures** - Coils fail regularly, especially under the higher loads of JCW tuning.

The good news? Most of these are well-understood fixes in the Mini community, and parts are readily available. The JCW package itself doesn't introduce unique failure modes beyond stressing the existing R53 weak points a bit more.

Would you like me to help you find similar track-ready Minis, or do you have questions about any specific issue?

Lot CCA0722: 2004 Mini Cooper S John Cooper Works

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Lot CCA0722: 2004 Mini Cooper S John Cooper Works

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